Semiconductor devices are used in a variety of electronic applications, such as personal computers, cell phones, digital cameras, and other electronic equipment. Semiconductor devices are typically fabricated by sequentially depositing insulating or dielectric layers, conductive layers, and semiconductive layers of material over a semiconductor substrate, and patterning the various material layers using lithography to form circuit components and elements thereon. Many integrated circuits are typically manufactured on a single semiconductor wafer, and individual dies on the wafer are singulated by sawing between the integrated circuits along a scribe line. The individual dies are typically packaged separately, in multi-chip modules, or in other types of packaging, for example.
The implementation of silicon-on-insulator (SOI) technology is one of several manufacturing strategies employed to allow the continued miniaturization of microelectronic devices, which may be referred to as extending Moore's Law. Reported benefits of SOI technology relative to silicon (bulk complementary metal-oxide-semiconductor (CMOS)) processing may include, for example, lower parasitic capacitance due to isolation from the bulk silicon, which improves power consumption at matched performance, and resistance to latch-up due to isolation of the n- and p-well structures.
From a manufacturing perspective, SOI substrates are compatible with most fabrication processes. Indeed, an SOI-based process may be implemented without special equipment or significant retooling of an existing factory. Although existing devices and methods for forming the SOI-based process have been generally adequate for their intended purposes, they have not been entirely satisfactory in all respects.